When the player tries to use a spawn egg in a position that is blocked by a projectile's hit collision (not it's hitbox, but the box used for hit/deflection detection), the entity will not be spawned but the hand animation plays. This issue closely relates to MC-208427 MC-223023 MC-167039 and may be the same core issue, but was reported standalone.

Steps to Reproduce:

1. Summon a fireball above the player

   /summon minecraft:fireball ~ ~2 ~
   

2. Try and spawn an enderman below the fireball, using a spawn egg

Observed Behavior:

The entity is not spawned, but the hand animation plays.

Expected Behavior:

The player would either be able to summon the entity properly through the collision box, or the entity should not be summoned and the hand animation would not play.

Screenshots/Videos:

SummonUnderFireball.mp4

Notes:

As stated above, related to MC-208427 MC-223023 MC-167039